IL3 and CD4+/CD56+ hematodermic neoplasm: CD123 targeting represents an effective therapeutic option for BPDCN patients and tagraxofusp, a drug based on a genetically engineered diphtheria toxin fused with IL-3, has shown robust activity and BPDCN was the first IL-3Rα targeting agent approved for the treatment of a hematological malignancy.